How do I change back to my X-session (GUI) tty?
My screensaver unlock screen got frozen, and fishing around I found that I could use CtrlAltF2 to switch tty's and get a (text only) terminal login.
The helpful pages that mentioned this, didn't however mention how to get back to my normal ubuntu GUI session. How do I do that??
Your graphical session is usually located at either Ctrl+Alt+F7 or Ctrl+Alt+F8. For me, running Ubuntu 13.04 it is F7.
A related, interesting read: What does "Ctrl + Alt + F12" do?